Field of the Disclosure
The present disclosure relates to a display device, and more particularly to a backplate and a foldable display device including the same. Although the present disclosure is suitable for a wide scope of applications, it is particularly suitable for a backplate and a foldable display device where a physical border line is not recognized even when the backplate includes different materials.
Discussion of the Background
Recently, as the information society progresses, display devices processing and displaying a large amount of information have rapidly advanced and various flat panel displays (FPDs) have been developed. Specifically, the FPDs such as a liquid crystal display (LCD) device, a plasma display panel (PDP) device, a field emission display (FED) device, an electroluminescence display (ELD) device and an organic light emitting diode (OLED) display device having superior performance with a thin profile, a light weight, and a low power consumption have been substitutes for a cathode ray tube (CRT).
Since the FPD uses a glass substrate with a heat resistance during a fabrication process, there exist limitations in the light weight, the thin profile and the flexibility of the FPD. As a result, a flexible display device which performs a display function even when bent by using a flexible material such as plastic instead of glass has been researched as a next generation FPD.
The flexible display devices may be classified into: an unbreakable display device which has a relatively high durability; a bendable display device which is capable of being bent; a rollable display device which is capable of being rolled; and a foldable display device which is capable of being folded. The flexible display device has advantages in a space application and interior decoration and design and has various other applications.
Specifically, a foldable display device which is carried in a folded state and displays an image in an unfolded state. The foldable display device may be applied to a television and a monitor as well as a mobile device such as a mobile phone, an ultra mobile personal computer, an e-book and an e-paper. The foldable display device includes a display panel for displaying an image, a backplate under the display panel for supporting the display panel and a cover window over the display panel for protecting the display panel.
Since all of the display panel, the backplate and the cover window are formed of a very thin film for the foldable display device to be folded and unfolded, the foldable display device has a relatively low impact resistance. Recently, for improving the impact resistance of the foldable display device, the backplate where a folding region is formed of a soft material and an unfolding region is formed of a hard material for rigidity has been suggested.
However, although the impact resistance of the unfolding region is improved, the impact resistance of the folding region is not improved. Specifically, since the backplate includes different materials of the soft material and the hard material, a physical border line between the folding region and the unfolding region is recognized through the display panel due to a step difference between the different materials or a difference in pressing property between the folding region and the unfolding region.
FIGS. 1A and 1B are views showing display panels without and with a backplate, respectively, according to the related art.
In FIG. 1A, a lamp image reflected in a display panel without a backplate has a straight shape without a bent portion. As a result, a physical border line between a folding region and an unfolding region of the display panel without the backplate is not recognized.
In FIG. 1B, a lamp image reflected in a display panel with a backplate formed of different materials has a straight shape including bent portions A. As a result, a physical border line between a folding region and an unfolding region of the display panel with the backplate is recognized, and a display quality of the display panel can be deteriorated.